阻塞型睡眠呼吸暂停综合征患者早期左心房结构和功能改变的临床研究

Early changes of left atrial structure and function in patients with obstructive sleep apnea syndrome

目的用超声心动图评价阻塞型睡眠呼吸暂停综合征（OSAs）患者伴或不伴左室肥厚（LVH）左心房结构和功能的早期改变。方法根据左心室质量指数将91例OSAS患者分为无肥厚组（64例）和肥厚组（27例），同时设对照组（40例）。用二维斑点追踪超声心动图（2D-STE）获取心尖四腔和两腔左心房应变和应变率曲线图像。测量各组受检者左心房整体长轴收缩期应变（Ss）和应变率（SRs）、舒张早期应变和应变率（Se、SRe）、舒张晚期应变和应变率（Sa、SRa），记录左心房时相容积并计算排空分数，用二尖瓣舒张早期峰值流速与二尖瓣环舒张早期运动速度之比（E／e’）评估左室舒张功能。结果与对照组比较，无肥厚组左-0房容积和硬度指数增大，Ss、SRs、Se和SRe减低，SRa增加，总排空分数（TEF）和被动排空分数（PEF）减低、主动排空分数（AEF）增加（均P〈0．05）；两组E／e’差异无统计学意义（P〉0．05）。肥厚组舒张功能减低，左心房容积、硬度指数、三个时相的应变、应变率以及排空分数与无肥厚组和对照组相比变化均更加显著。睡眠呼吸暂停低通气指数（AHI）与Ss、SRs、Se、SRe、TEF和PEF呈负相关。结论OSAS患者左心房扩大，左心房顺应性减低，储器和管道功能减弱，而泵功能增强，左心房结构和功能重构早于LVH和左室舒张功能障碍，并随左室肥厚发展而进一步加重。

Objective To investigate the early changes of left atrial structure and function using echocardiography in obstructive sleep apnea syndrome（OSAS） patients with and without left ventricular hypertrophy（LVH）. Methods Echocardiography was performed in 91 OSAS patients （64 without LVH, 27 with LVH）, and the results were compared with those from age-matched and gender matched controls （n = 40）. All subjects were examined with two-dimensional speckle tracking echocardiography （2D-STE） to obtain the apical four chamber and two chamber left atrium（LA） strain and strain rate curve image. Systolic strain and strain rate（Ss, SRs）, early diastolic strain and strain rate（Se, SRe）, late diastolic strain and strain rate（Sa,SRa） were measured. Phasic LA volumes and empty fractions were calculated. The ratio of peak early diastolic mitral inflow and annulus velocity（E/er） was used to estimate left ventricular diastolic function. Results Compared with the control group, LA volume, LA stiffness index, SRa and active empyting fraction （AEF） increased,Ss,SRs, Se, SRe, total empyting fraction （TEF） and passive empyting fraction （PEF） decreased in none LVH group （ P 〈0.05）. Importantly, diastolic function was relatively normal in this subgroup without LVH （ P 〈 0.05）. Diastolic function decreased in LVH group, and the changes of left atrial structure and function like above mentioned were more significant. The apnea hypopnea index （AHI） was found to be negatively correlated with Ss, SRs, Se, SRe, TEF and PEF. ConclusionsOSAS is associated with LA remodeling and dysfunction that occurs before the development of LVH and left ventricular diastolic dysfunction, and it will be further aggravated along with the development of LVH.